## QuickCheck Generators

2012-11-20 21:07:37 GMT

I have data Tweet = Tweet { user :: String, text :: String, retweets :: Double } deriving (Show) data TweetSet = NoTweets | SomeTweets Tweet TweetSet TweetSet and trying to create some generators for testing, with instance Arbitrary Tweet where arbitrary = liftM3 Tweet arbitrary arbitrary arbitrary instance Arbitrary TweetSet where arbitrary = sized set' where set' 0 = return NoTweets set' n | n>0 = oneof[return NoTweets, liftM3 SomeTweets arbitrary subTweets subTweets] where subTweets = set' (n `div` 2) but wondering how I would go about generating a random TweetSet that contains a known random Tweet I later have reference to and I would also assume the known Tweet to be placed randomly. Then I could test a contains function. Thanks(Continue reading)